The document summarizes the anatomy and functions of the central nervous system and its parts. It describes the three meninges (dura mater, arachnoid mater, pia mater) that protect the CNS. It then discusses the structures and functions of the brainstem, cerebellum, diencephalon, and cerebral cortex. It also outlines the somatic sensory and motor pathways, as well as the autonomic nervous system including its sympathetic and parasympathetic divisions.
9. The somatic nervous pathway is made up of nerves that connect to the skin, sensory organs and all
skeletal muscles. The system is responsible for nearly all voluntary muscle movements as well as for
processing sensory information that arrives through external stimuli, which are things like hearing, touch
and sight.
The somatic motor pathways include smooth muscle, cardiac muscle, and glands. The two divisions
would be sympathetic division and parasympathetic division.
Parietal lobe
Frontal lobe
Occipital lobe Thalamus
Cerebellum
10. Cerebrum
ain
Cervical Cerebellum
Enlargement
Spinal
Nerve
Cord
Root
ain
ain
Membranous covering
(meninges)
Lumbar Enlargement
Filum terminale
13. Pg. 418- 419 Dermatomes- “Each skin surface area supplied by sensory fibers of a given spinal nerve is
called a dermatome, name that means “skin section.” Image (4)
14. Pg. 421 Myotomes- “skeletal muscle or group of muscle’s that receives motor axons from a given spinal
nerve. “ Image (5)
17. Autonomic Nervous System
Function: Pathways in the ANS carry
information to the visceral effectors which are
the smooth muscles, cardiac muscles, and
18. glands. It powers itself without our conscious
knowledge. It has two efferent divisions
including the sympathetic and
parasympathetic division. They are made up
of autonomic nerves, ganglia, and plexuses.
The parasympathetic division is the “rest and
repair” division that uses acetylcholine it’s
transmitter to slow the heartbeat, promote
digestion etc. Parasympathetic stimulations
have different effects on effectors such as
constriction of bronchioles and contraction of
urinary bladder. The sympathetic division
opposes the parasympathetic impulses which
would for example, raise the heartbeat.
19. Sympathetic stimulations have effects like
dilation of bronchioles and relaxation of
urinary bladder. As a whole, the ANS
functions to regulate autonomic effectors to
maintain homeostasis. For example, X Vagus
goes to the heart and controls the heartbeat,
while the IX Glossopharyngeal goes to the
lungs and control respiratory actions.